


Heartbeat, Heartbreak

by LoneWulffe



Category: Supergirl (TV 2015)
Genre: (you should know how this ends already), Angst, F/M, Mentioned Clois
Language: English
Status: Completed
Published: 2017-09-12
Updated: 2017-09-12
Packaged: 2018-12-27 02:47:48
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 8,038
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12072045
Author URL: https://archiveofourown.org/users/LoneWulffe/pseuds/LoneWulffe
Summary: She listens, and she hears. (Until she doesn't.)





	Heartbeat, Heartbreak

**Author's Note:**

> No betas were tormented for the sake of this fic so please direct all error reports my way.
> 
> The title comes from a track on the Persona 4 soundtrack.
> 
> This ended up being more of a recap piece compared to my previous work but I hope I added enough original content to prevent it from becoming a glorified transcript. Once again, I hope you have your Karamel Season 2 Roadmap on hand (with the angst parts highlighted).

> _The stars, the moon, they have all been blown out_
> 
> _You left me in the dark_
> 
> _No dawn, no day, I'm always in this twilight_
> 
> _In the shadow of your heart_
> 
> – _Florence + The Machine, Cosmic Love_

 

* * *

 

In Kara's defence, it's not like she'd started doing it intentionally. (This is actually how she starts the conversation months later.)

She can remember the moment leading up to it with startling clarity. It's something which she's actually less than grateful for because on the list of memories she'd like to be able to replay perfectly, being stuck in a cage alongside Mon-El and at the mercy of Cadmus was most definitely not even up for consideration.

The only logical conclusion she can come to is that in that moment, she'd tried to be so prepared for whatever tricks Lillian might pull that she'd pushed her senses into overdrive.

In hindsight, it had only made the experience worse because she'd ended up watching Lillian shoot Mon-El in slow motion while the combined loudness of the gunshot, his howl of pain and her own scream of panic had been deafening. Her anxiety over his wellbeing had unintentionally caused her to focus all her adrenaline-heightened senses on him. An X-ray scan had revealed to her the sickening effect the lead was having on his flesh and her ears had honed in on his laboured breathing as well as the erratic sound of his heartbeat. She had clung to that sound in particular and used it as a way to reassure herself that he was okay for now as she tried to figure a way out of this situation-

-only to hear Lillian threaten to put an end to that permanently.

There really had been no choice after that.

So she'd agreed, all the while ignoring his weak pleas to the contrary, and had done as Lillian demanded.

With the loss of her powers, her ability to keep track of his heartbeat had understandably gone with it and that had been that.

 

* * *

 

...is what should've been the case.

It's been hours and now they're safe and sound in her apartment with him resting on her couch, his leg propped up and covered with the ice pack she'd accidentally all but smashed into the still-healing wound when Alex had surprised her with her arrival. He's joking like usual and they're actually having a nice conversation where she doesn't feel like breaking something over his thick skull for once. All's right with the world.

She's still (rightfully) worried. Just a little.

It's a reasonable fear, she tells herself. He could've died. _Both_ of them could've died, in fact, if not for Jeremiah's help. She finds it hard to believe Lillian wouldn't have taken advantage of such a valuable opportunity to rid herself of one Kryptonian, much less have any reason to keep Mon-El alive after having gotten what she'd wanted.

Now that she knows he's vulnerable to _lead_ of all things and could die if any stupid thug with a gun managed to score a lucky shot and hit him, it's only natural for her to worry, right?

Maybe it's the residual fear and uncertainty coupled with her budding sense of mild paranoia that prompts her next act. Maybe she just wants a little reassurance that this isn't some fever-dream and they're really alive. Whatever the reason, she finds herself focusing her hearing on his heartbeat, silently thankful that his alien physiology gives it a rather unique rhythm-

Winn's voice breaks her concentration, telling her that Alex needs her help in the kitchen, and for that she's rather grateful; what had she been _thinking_? Listening to his heartbeat had been somewhat excusable when she'd done it unintentionally before but what reason does she have to be consciously doing it now?

Quietly praying she doesn't look as flustered as she feels, she makes a silly quip about a superhero's work never being done and scuttles over to give her sister a hand with dinner. Alex unwittingly answers her prayers for a distraction by making her usual comment about how this is the closest either of them will ever come to cooking anything edible. It prompts a laugh out of Kara and a trip down memory lane of the time they'd tried to surprise Eliza with breakfast on her birthday but had burnt even the toast to a crisp.

Everything after that goes normally – well, as normal as possible when your dinner discussions involve nefarious alien-hating organisations headed by your best friend's mother which are possibly holding your adoptive father prisoner – and Kara manages to forget about her earlier actions... until it's time to see everyone off.

James and Winn leave rather early, complaining that all the food has made them sleepy. Alex makes a snarky comment about keeping their guard up on their way home that must be some kind of inside joke because they just throw her dirty looks before making themselves scarce. Kara decides it's got nothing to do with her so she lets it slide and focuses on clearing up. To her credit, Alex helps out a little before telling Kara that she has to get Mon-El back to the DEO and head home herself. The medical staff had only agreed to let him leave for a few hours and had demanded he be brought back for overnight observation – an order neither Danvers sister feels like disobeying.

Maybe it's that reminder that he almost died today that prompts it. (Maybe there's something else too, but she doesn't realise it. Not yet, anyway.) The why doesn't really come up in that moment as she's seeing them off; Alex leaves first to bring her car around so Mon-El won't have to hobble so far and she helps him get down to the ground floor and waits with him on the pavement. It's nice and peaceful and both of them are relaxed enough that they don't feel the need to fill the silence.

That's when she finds herself listening to his heartbeat. Again.

She barely keeps it together when Alex's car materialises in front of her and the two of them shovel Mon-El into the back seat. It proves to be no small feat on her part to act perfectly normal as she wishes them goodnight and watches the car speed off before marching robotically back up the stairs and into her apartment.

His heartbeat is still resounding in her ears.

 _...Oh no_ , she thinks as she finds herself consumed with a slowly growing panic.

 

* * *

 

It takes her thirteen rounds of pacing which she is sure has worn a nice pattern on the floor of her living space before she finally works up the courage to call the only person she can talk to about this.

“Kara?” Kal's voice is hushed over the phone – understandable, considering the late hour. He must be trying not to wake Lois. “Is something wrong?”

“Hey, sorry about calling so late. And no, it's nothing serious,” she's quick to reassure him. “I just...” She flounders for a moment, lost as to how to verbalise her predicament in a way that won't make her sound like a creepy stalker or something.

 _But you kind of are coming across like that_ , a small voice at the back of her mind points out. She squashes it with a vengeance.

“Kara? You still there?”

Kal's worried query snaps her back to reality. “Yeah, sorry.” She sucks in a fortifying breath and decides to just dive in. “I was just wondering if... I know this is going to sound weird, but... do you... uh... do you listen to Lois' heartbeat? As in use your powers to do it, not... the other way.” _Yeah. Totally not awkward. Way to go, Kara._

There is silence on the other end of the line. It just serves to highlight the sound of Mon-El's heartbeat – somewhat muted now thanks to the distance between them but still there nonetheless – which is kind of the problem. She fidgets and tries to shut it out to no avail.

“...Well.” He coughs then clears his throat before continuing. “I have to admit I wasn't expecting that question.”

“It's okay if you don't want to answer!” she responds hastily, already regretting calling him in the first place. “I shouldn't have asked in the first place-”

“Kara, it's okay,” he calmly cuts her off. She can't be sure but it sounds like he's using his patented 'trust me, I'm Superman' voice on her which rankles her a little. “We're family; I'm here for you in every way just as you are for me.”

Okay, maybe she'll let him off the hook for doing that just this once. “I know. Thanks.”

“You're welcome. About your question though... yes, I do,” he confesses rather sheepishly. “Don't tell Lois I said this or she'll probably kill me but she has this ridiculous tendency to always get into trouble even when she's not chasing a story. There was this one time she went to try out this new cafe for lunch by herself and before I knew it she was smashing a plate over the head of the guy trying to stick up the place. I started listening out for her heartbeat early on without telling her but I did come clean later. She gave me hell for it at first but finally just let me be because she knows hearing it reassures me that she's okay.”

“I see.” Not for the first time, she finds herself wishing that she could have what her cousin has with Lois. As soon as the thought pops up in her head, however, she shakes it out; she can't let herself get distracted from her true objective. “Did you... uh, try to stop doing it? At the beginning, I mean?”

“I did, of course. It's not like I actively chose to start in the first place. Worrying about her was like second nature though so I found myself doing it again and again without realising it,” he admits, pausing for a moment before speaking again. “If you don't mind me asking, what brought this on? Did you accidentally start doing it yourself?”

There's no benefit in not telling the truth so she decides to be honest. “Yeah, I did,” she groans and flops down on the couch. “I was hoping you could teach me how to stop.”

He chuckles. “Sorry, I wish I could.” Another pause. “Is it Alex?”

Oh, she is _so_ glad he can't see her face right now. “Um, yeah,” she lies and decides she'd better find a way to politely hang up before he somehow picks up on her deception. “Anyway, I'll let you go back to sleep already. I should probably go sleep too so... goodnight!”

If her abrupt termination of their conversation makes him suspicious, Kal doesn't show it in his voice. “All right,” he responds warmly. “Goodnight, Kara.”

The click that signals the end of the call should have heralded silence descending around her once more... except there it is – that steady beat thrumming at the edge of her consciousness that only grows louder the more attention she pays to it.

Rao above, what is she going to do about it?

 

* * *

 

In the end, Kara decides to treat it like some kind of background music to her life. After all, she's a superhero; it shouldn't be too hard to imagine she's living in some kind of CW show world, soundtrack and all, right? A very drum-heavy soundtrack, that is, but still. All she has to do is convince herself of that and she'll be fine. Probably. (She'd tried not worrying about Mon-El but that had proved to be futile every time she remembered that Cadmus now not only knew he was an alien and his fatal weakness but also that he was closely associated with her.)

She reasons that it's (mostly) fine as long as she's not using it to track him like some sort of unorthodox GPS system... and viciously crushes the voice at the back of her mind when it notes that it's still kind of wrong when he has no idea she's doing it in the first place.

There will come a day, she swears to herself, when she will admit it to him and he will understand. At least, that's what she hopes anyway.

...Maybe she'll just put the matter aside for now. In the meantime, there are other more important things to focus on like Thanksgiving. Which she'd invited him over for somewhat nervously. She'd even gone to the effort of trying to include him in the preparations by asking him to bring stuffing.

When he shows up with the inedible kind, she's not sure if she's supposed to feel exasperated at herself for forgetting that he's still so clueless about so many Earth things or charmed that he clearly hadn't hesitated to destroy his mattress to fulfil her vague request.

She feels a lot less charmed when he starts hitting on Eliza.

Except Eliza laughs at her and corrects her, saying the most ridiculous things in the process. There's no way Mon-El likes her and especially not in _that_ way. Even so, her gaze slides over to the living room and he looks over at her just then. The eye contact just highlights the drumming noise inside her head so she shyly looks down and tries not to think too much about it. Not that it helps when they end up sitting next to each other and he gives that really sweet speech because the beat just gets a little bit louder. (Or is that her own heart she's hearing? She promptly decides she doesn't want to contemplate _that_ either.)

In a way, she's glad that portal appears. The more things she has on her mind that keep her from thinking about the endless drumming she hears, the better.

 

* * *

 

Kara is halfway through her report about the admittedly limited information she'd gleaned from Lena when she detects a spike in Mon-El's heart rate. Her first instinct is to worry but then she becomes aware of the lateness of the hour and considers that there might be... other explanations for this occurrence that don't involve his life being threatened.

For some reason, the idea of him possibly getting intimate with someone is making her stomach churn.

“Kara?” J'onn's voice draws her out of her thoughts and she looks up to find him, Alex and Winn looking at her with concern. “Is something wrong? You trailed off mid-sentence.”

Oh. “Uh, sorry,” she stutters, unsure how she can play this off. “I just thought of... something.”

Unfortunately, her vague statement triggers the kind of reaction she had wanted to avoid. “Did you figure something out?” Alex asks, her tense voice and posture clearly communicating her readiness for action.

Crap. “Um, no, not really,” she stumbles over her words as she begins panicking. “It's probably not even relevant-”

As if in answer to her silent prayers for divine intervention, her phone chooses that moment to ring. However, the name on her screen just confuses her. Why would he be calling her if he was in the middle of... oh god, he hadn't somehow accidentally dialled her number while making out with whoever it was, had he? At least, she certainly doesn't want to think that he'd do it intentionally because that would just be so wrong on so many levels.

There's only one way to find out and she's not really looking forward to it. Pressing the button and putting her phone to her ear, Kara mentally prepares herself to hear something that would make her demand J'onn wipe her memory afterwards.

“They're dead.”

The blood in her veins freezes. Mon-El's heart is still racing but Kara is very sure hers has stopped outright. “What?” she blurts out, only vaguely aware that she might be shouting. “What do you mean, 'they're dead'?” Almost immediately, she focuses on his heartbeat to try and determine his location; if he's in danger, she has to find him _now_.

“Wait, who's dead?” Winn exclaims in alarm. “What's going on?”

“They're dead,” Mon-El repeats somewhat distantly. He must be in shock. She knows she is anyway. “The... the aliens.” That detail and the direction from which she's detecting the thundering sound of his racing heart means he's likely at the bar but she can't be completely sure; she's aware that there are a few unofficial alien community centres in that area and she can't risk being wrong. Not when his life and potentially others might hang in the balance.

“Kara, put it on speaker,” J'onn orders her and she complies somewhat mechanically even as she tries to figure out how long it'll take to just fly over and search for him manually. “Mon-El, you need to tell us where you are and what happened in detail.”

It's clear that Mon-El is barely cognizant of the fact that his call to her has turned into a transmission to the entire DEO because he keeps speaking in that same shell-shocked manner. “I'm at the bar.” So she'd guessed right. “He was here. I fought Henshaw. I fought him but he left and... and there was screaming and this weird smoke was in the air when I went back in and I just... found them all lying dead on the floor.” A beat. “Grife, J'onn. They're all _dead_.”

She can't take any more of this. “Stay put,” she tells him as she puts her phone down on the table and turns to make her way to the balcony. “I'm coming to get you.”

“No, you're not,” J'onn tells her, stopping her in her tracks. “We don't know what we're dealing with here so I'm going to send a team there to investigate and bring Mon-El back here. You, on the other hand, have to stay put.”

“But J'onn-” she starts to protest; Mon-El needs her help. Why can't he see that?

“J'onn's right, Kara,” Alex cuts her off. “There's a lot we don't know so we have to err on the side of caution. I'll lead the team myself, okay? We'll bring him back and make sure he's fine. Please, trust me.”

There's no way to argue with that so Kara settles for changing into her super-suit and pacing around the command centre until Winn begs her to stop because she's making his anxiety levels shoot through the roof. All the while, she focuses on Mon-El's still-racing heartbeat as she beats herself up internally over her earlier uncharitable assumptions. God, how could she have thought so badly of him when he'd been fighting for his life and trying to do something actually heroic? She's never going to forgive herself for this.

Thankfully, he seems to be okay – minus the Hazmat escort, that is – when Alex finally returns with him in tow although she's less than pleased to hear that she's to be put in time-out along with him for her own protection. Oh well. This is a good time to start making it up to him even if he doesn't know – and won't ever find out if she's lucky – what she'd thought he'd been up to. Everyone likes Monopoly, right?

Even so, Kara can't help but think of where her thoughts had gone and how she'd felt about that imagined scenario even as they joke around over the board game. Eliza's statement on Thanksgiving and the steady beat of Mon-El's heart – she's so glad its rhythm has more or less gone back to normal – continue to ring inside her head until she can't take it any longer.

She has to know.

“Hey, you don't... uh...” she starts talking before she can help herself, “you don't like me, do you?”

The look he gives her conveys nothing but confusion. “Of course I like you,” he answers readily.

Great. Too vague. “No, I mean like, you don't...” she trips over her own words, “...like me like me.” Rao, this is so embarrassing. Maybe if she prays hard enough the floor will open up and swallow her whole.

That just serves to confound him even more if his expression is any indication. “Like you like you?” he repeats with that 'I'm being polite but you've lost me' smile of his. “Sorry, English is my second language...”

She could try to play this off but as they say, in for a penny... “My mom Eliza,” she starts haltingly as she nervously toys with the game piece in her hand, “she... she thought you were being extra-nice to her on Thanksgiving?” Once more with the vagueness. _Get it together, Kara._ “That's like a thing that boys on this planet do. They're nice to the moms of...” God, this is hard. Why did she think this was a good idea again? “...of girls they have crushes on. S-Sometimes.” What in the world is she even babbling? Where's an alien invasion when you need it?

“Crush...?” Mon-El's utterance gets her attention but when she looks up she finds him still looking very much confused by her words. His heartbeat is also still very much steady in its rhythm. “Sorry, I'm not... I'm not following.”

...That's it. Enough with the subterfuge. “You don't want to mate with me, do you?” she asks him point-blank.

Okay, _now_ his heart is racing. But it could mean anything. He's giving her an unreadable look which transforms into a smile and suddenly he's laughing. She still finds herself smiling back expectantly anyway. “Um,” he coughs awkwardly, “I mean, have you seen the women that I've been attracting – Earthlings and otherwise – since I've been on this planet?”

Oh. Well, good thing she asked then. That's relief she's feeling, right? “Uh huh,” she says and busies herself with continuing the game so she doesn't have to pay any more attention to his still-racing heart. “Thank you for the clarification.”

But then he doesn't stop coughing and she comes to the horrifying realisation that his heart is racing for an entirely different and more dangerous reason.

 

* * *

 

Kara isn't entirely sure how she's become so familiar with the normal rhythm of Mon-El's heartbeat that the currently irregular drumming reaching her ears sounds so wrong to her but now is not the right time to think about that. Actually, there are a hell of a lot of things she could be thinking about right now – her father's role in the current nightmare scenario she's living in, J'onn's situation, Cadmus' plot, Lena's possible involvement – but in this very moment, she just worries that Mon-El might die and she'll never hear his heart beating ever again.

The thought alone terrifies her to her core. (The why behind that dread eludes her.)

Of course, he just has to choose that very second to wake up and start joking with her like nothing's wrong. She appreciates it for what it's worth although he's surprisingly the one who brings up the elephant in the room instead of her.

Except he's doing it in that 'I have made peace with my fate' way and even her reassurances sound hollow to her. Her guilt over her father's and by extension her part in his suffering causes her to confess her family's crimes to him but all he does is reassure her like _she's_ the one who needs it-

-and then he surprises her by kissing her and she surprises herself by kissing him back and _oh_ , that drumming noise in her head is so loud and clear she wonders if he can hear it too.

It's not until he's passed out on the bed again that she realises that the symphony of heartbeats thundering in her ears is a combination of his and her own.

 

* * *

 

She needs to forget about the kiss just like how he doesn't seem to remember it. She also needs to stop listening to Mon-El's heartbeat starting from yesterday.

Unfortunately for Kara, she fails spectacularly at both.

Praying to Rao for help proves to be a bad decision because the next thing she knows, she's jumping through a portal and standing under the bright rays of a red sun. To top things off, Mon-El ends up following her. So much for being free of the sound of his heartbeat when he's right there to remind her of his existence and The Incident she's trying so hard to forget.

Rao clearly has a twisted sense of humour even if at the end of the day he's kind enough to ensure they get back home in one piece with the rescued humans in tow. (She does her best not to pay attention to the fact that the moment she'd regained her powers thanks to the yellow sun grenade, she'd gone right back to listening to his heartbeat.)

Then he shows up at her apartment – bearing gifts, no less – and tells her he's ready to embrace the superhero life. As happy and proud as she is of him making this decision, a part of her is aware that this just means he'll be actively in danger from now on and she worries about him just a little more. While it isn't her primary motivation for doing it, this realisation contributes to her insistence that he listen to her. She's stronger and more experienced; she can handle whatever comes her way a lot better than he can.

Which of course seems to have been the wrong thing to so much as think because the universe decides to reintroduce Livewire to her life. And of course he doesn't listen to her. And of course they fight about it. And of course her brain decides this is the perfect time to bring up The Incident and ask him if he likes her.

And of course it's when everything's mostly gone back to normal that he shows up at her apartment to confess to not only remembering the kiss but also the reason he'd refused to listen to her orders.

His heartbeat is steady and deceptively calm throughout his entire speech.

In contrast, the drumming in her ears that is her own heart is gradually increasing in both speed and volume.

It's rather amazing, she thinks long after he's said his piece and left, that he'd just given her an out so easily. But this is good. This is something close to perfect. Because she doesn't like him like that, right? It's not like any of her actions recently could ever be construed that way, right?

Except the drumbeat of his heart is still there at the edge of her consciousness and now so is hers, keeping time with his, and all she feels is an inexplicable sense of emptiness.

 

* * *

 

Under normal circumstances, it should have been easy – or at the very least easier – to just shove all this out of her mind in an effort to force things to go back to the way they were before. Unfortunately, her attempts to do so are hampered by the fact that she still hears Mon-El's heartbeat resounding in her ears and there seems to be nothing she can do to block it out. When she tries to move past it, things just turn out worse.

Attempting to talk to him about his confession ends... badly.

Praying to Rao for help seemingly results in White Martians infiltrating the DEO. (Kara wonders if she should consider revising her religious beliefs at this rate.)

Finally admitting to herself that she might actually like-like him thanks in no small part to Alex gets her a dose of 'too little, too late'.

Well. She can always just avoid him. And if she hears an increase in his heart rate anytime soon, she's going to imagine he's getting into a bar fight instead of... other things that may or may not involve Eve.

Her game plan lasts up until Eve drops her little bombshell about them no longer dating and leaves her with a wink along with none-too-subtle hints about what she thinks about the two of them getting together.

It's nice to know someone actually has confidence in her love life because she sure doesn't considering the stellar results she's been getting thus far. Still, Eve's words and encouragement compels Kara to confront Mon-El about it... although in hindsight she thinks she should've picked a more suitable time to do it instead of the middle of the matter involving Lena's wellbeing and Lillian's latest plot that she has worry about.

 

* * *

 

Mon-El's heartbeat is soothingly steady in contrast to hers at the start of her confession although that changes quickly enough. Like hers, his gets louder and louder with every step she takes that brings her closer to him until the sound of their hearts in sync fills her head up and leaves her at a loss for words.

“Hi,” he breathes.

“Hi,” she murmurs back and tilts her head up to kiss him.

Which is of course when some strange guy literally appears out of thin air in her apartment and not only confuses the hell out of her by confessing his feelings but also sends her into a full-blown panic when he makes Mon-El disappear.

“What did you do with him?!” she demands even as she reassures herself that he must be relatively fine because she can still hear his heartbeat somewhere in National City. She gets her answer soon enough – thank Rao he's in the DEO and not somewhere more dangerous – but that still leaves her with the creep-shaped problem in her apartment.

A creep-shaped problem which not only refuses to get out of her life but also threatens to ruin it entirely with his outrageous demands and attempts to kill Mon-El. On Valentine's Day no less. To be fair, Mon-El's idiotic and frankly patronising efforts get on her nerves too but at the rate things are progressing, she has more to worry about than his ego.

So she breaks his heart to save him and could almost swear she's broken her own in the process because the look on his face is causing her physical pain. Even so, she reassures herself that this is the right course of action by reminding herself that she'll do whatever it takes to ensure his physical heart keeps beating.

 

* * *

 

Her crazy plan works somehow. Now if she could just find a way to salvage the potential for something between her and Mon-El...

Of course, it's just as she's figuring out a way to fix things between them that he surprises her by showing up himself and what transpires afterwards feels like a do-over of both their first confessions rolled into one.

Unlike both those instances, this one goes much better.

Much _much_ better.

(This time, falling asleep to the sound of his heartbeat is much more convenient and pleasurable because she has her ear pressed against his chest right above his heart. She is equally happy to wake up the same way.

She could get used to this, she thinks.)

 

* * *

 

Jeremiah happens.

It hurts.

Kara thinks she might hate Mon-El just a little for being right, but mostly she hates herself for not listening to him until it had been far too late.

That familiar drumbeat comes steadily closer and she finds herself somewhat grateful that she hadn't bothered to lock the door when she'd come home because that means she doesn't have to get up and open it for him.

She's even more grateful when he simply takes one look at her and decides to not say anything along the lines of 'I told you so', opting instead to ask her what she needs.

It's a long list, if she's being truthful, but right now there's only one thing she wants from him. “Just be here with me,” she whispers.

He seems to understand perfectly and in that moment there are no words to describe how thankful she is that she has him because she can't imagine having to go through this point in her life alone.

“Come here,” he urges quietly and she all too readily complies, curling against him so she can take comfort in the sound and feel of his heart beating in his chest.

(Even though the moment is over too soon, she gets her wish to wake up in bed with him eventually, his arms around her and his body warm and solid against hers as the drumbeat of his heart continues to resound in her very being.)

 

* * *

 

“I have a confession to make,” Kara starts quietly as they're lying in bed together.

“Hmm?” Mon-El's soft drowsy hum which indicates he's on the verge of falling asleep causes his chest to vibrate rather pleasantly. It adds a strange but not unwelcome element to the rhythm of his heartbeat... and she really should focus or she's going to lose her nerve.

“In my defence,” she says, “it's not like I started doing it intentionally.”

“Mm... doing what?” Great, he's really going to fall asleep within the next ten seconds at this rate. Maybe she should've tried having this conversation during dinner or something.

Sighing, she prods his chest and is rewarded with a pained grunt. “Please stay awake. I'm trying to have a serious conversation here.”

“Okay, okay,” he groans as he shifts in a futile and half-hearted attempt to escape her assault. “I'm listening. What did you do?”

“What I'm still doing,” she corrects him, determined to be completely honest about just how badly she's been abusing her powers where he's concerned. “The truth is... I've been listening to your heartbeat.”

The silence that descends around them worries her – what if she's made him uncomfortable and he wants her to stop? – but he speaks up just as she is about to blurt out a rambling apology. “...That's it? I guess that explains why you always insist on sleeping on the left side of the bed and love to rest your head on my chest but I thought it was something more serious than that.”

...Okay, he's being really calm about this. It takes her a second to realise that in his groggy state, he must have misunderstood her. “No, you don't get it,” she huffs, annoyed at both him and herself, and regretfully gives up her current very comfortable position to prop herself up on her elbows so she can look him in the eyes. “I don't mean what I'm doing right now, pressing my ear to your chest. I mean I've been using my powers to do it. And I've been doing it since that time we got captured by Cadmus.”

“Oh.” He furrows his brows. “Why?”

“Um, well... that's...” She lowers her gaze and picks at his shirt in nervousness. “I was worried. About you. Lillian had just shot you and I needed to reassure myself that you were at least somewhat okay. After that, I guess I just... never stopped worrying. I mean, can you blame me? You always say I go looking for trouble but trouble just seems to find you-”

“Hey.” With that one word, he puts an end to her anxious babbling and she looks back up to find him smiling softly. “It's fine. I don't mind. If it helps put your mind at ease, go ahead and keep doing it.”

“Are you sure?” she asks somewhat disbelievingly, having never expected him to be so... accepting of her actions. “Don't you... I don't know, feel like I'm invading your privacy or something? I mean, I could use your heartbeat to track where you are if I concentrate really hard. Not that I do that often. Or at all. Well, maybe once or twice-”

“Kara.” This time, he makes sure to put an end to the deluge of words spilling out of her mouth by pressing a finger to her lips. “It's fine. I'm giving you permission. It's not like I go anywhere I don't want you to find out about and I want you to know that I'm here with you. I'm not going anywhere. Listen away.”

“You're sure?” she asks again, dubious but a little hopeful. It's becoming hard for her to contain her relief especially since she's not sure if she could stop even if he'd asked.

“I'm sure,” he manages to say before a yawn breaks his tender expression and the mood along with it. “Can we sleep now? I think you'll agree with me when I say it's been a long day.”

She can't argue with that so she wishes him goodnight and lies back down, ensuring that her ear is aligned with the right side of his chest where his heart resides.

 

* * *

 

Her happiness doesn't last. (Perhaps, Kara thinks bitterly, it was never meant to exist in the first place since it had been based on a lie.)

Fear for his wellbeing – of losing track of his heartbeat which she's come to rely on as a way of reassuring herself that he's alive and with her – drives her to follow him as he's transported up to the spaceship.

The truth she learns there turns the sound she cherishes into a curse she cannot purge from her soul no matter how hard she tries.

“I love you,” he tells her with tears in his eyes and it wasn't supposed to hurt when she finally heard those three words from him but it does. “With everything that I have, I... I love you.”

She can't take it – any of it – and she makes him leave but the drumming noise in her ears continues, strained but still ever-present. It drives her to dig up a set of Alex's old headphones, hunt down some of that atrocious music her sister used to listen to online and blast it at the loudest volume she can handle in an effort to drown it out.

It doesn't work.

In fact, the sound even follows her into the musical world, a ghostly echo underlining every line of every song. It irritates her at the start but as the story progresses and she finds herself confronted with her own failings – through words from her own mouth, no less – she finds comfort in it instead.

When he somehow manages to find his way into the musical and brings her back with a kiss of all things, she's entirely unsurprised to find that the echo she'd been hearing throughout her ordeal had been keeping perfect time with his actual heartbeat.

Maybe, she thinks, the sound had not been just her imagination after all.

 

* * *

 

“I didn't stop, you know,” Kara confesses quietly. They're back in her apartment, entwined around each other in bed as if allowing even a sliver of space to exist between them is unthinkable. (She had tentatively asked him to come home after they'd returned to their Earth, and the smile that had spread across his face at both her request and choice of words had been comparable to a sunrise.)

“Stop what?” Mon-El's voice is soft but still mostly alert; like her, he must not be feeling any particular urge to fall asleep anytime soon.

“Listening to your heartbeat.” She draws meaningless shapes across the plane of his chest even as she counts the beats and notes how they match the rhythm of her own like always. “To be honest, I tried to stop but I couldn't. I guess... I guess it's second nature to me now.”

He tightens his grip around her body for a brief moment in what she thinks could be reassurance. “I'm sorry. If things had stayed like that-”

“Stop.” She stills her fingers so that she can splay them across his chest and presses them down lightly to get her point across. “I was wrong for not being willing to put aside my prejudices and hearing you out in the first place. Besides, I made the decision to start listening to your heartbeat in the first place; you didn't ask me to so you have nothing to apologise for, okay?”

That earns her a light chuckle that she feels more than hears. “Okay. Have I ever mentioned how bossy you can be even when you're saying sorry?”

A small smile steals across her face against her will. “It comes naturally. I'm a Kryptonian, remember?”

This time, his laugh is a little louder. “Oh, I remember all right. But it's okay. I love you anyway.”

He says it so casually that she finds herself at a loss for words. She could say them back – just three simple words – right now. But the pain their breakup caused her is still too new and this moment seems too fragile. She wants the timing to be just right but most of all she wants to be sure that she means it in its entirety, full of nothing but happiness and free of lingering hurt, when she says it.

“I know,” she says instead and breathes an internal sigh of relief when he simply accepts her response.

Another time, she thinks. She'll tell him another time.

(This becomes a pattern. And she will come to regret this.)

 

* * *

 

“Don't go,” she pleads but Mon-El steps back anyway and it's all her fault – her and her stupid _naïveté_ – that they're both suffering right now. Then he vanishes along with Rhea and she can't tell which hurts more: the wounds caused by Rhea's Kryptonite sais or the deafening emptiness that has replaced the steady beat of his heart.

She can't lose him and tells J'onn exactly that. Even as she comes up with her admittedly insane plan to save him and everything plays out as intended for the most part, she doesn't let herself truly relax until their arms are wrapped around each other again.

“You came after me,” he murmurs, half in relief and half in wonder.

Kara revels in the solidness of him – the warmth of his body and the tightness of his hug – but most of all she revels in the sound of his heart beating strong in her ears. “Every time,” she whispers back in place of those three words. She doesn't want an audience around when she says it so she leaves it at that for now.

She forgets to say it again when they're safe and sound back in her apartment, lulled into thinking that she has all the time in the world to find the perfect moment to say them.

(She is wrong again, but she will not know this until it is too late.)

 

* * *

 

Kara knows the exact moment Rhea takes Mon-El – and Lena too, as she finds out later – when she once again stops being able to hear his heartbeat. It's fine, she tells herself as a way to stave off the rising wave of panic threatening to consume her. She can fix this just like she had before.

Except the stakes are so much higher this time around and when Alex proves to be more than ready to carry out the President's orders to blow up the ship while Mon-El and Lena are still on it, the steadily growing possibility that she will never hear that drumming sound that matches the beat of her own heart ever again threatens to break her.

Thank Rao for Miss Grant and her inspirational speeches.

...She's not sure if she's supposed to feel thankful for Lillian though. On one hand, the older Luthor woman represents a way for her to save her boyfriend and her best friend. On the other hand, she's _Lillian_.

It's a good thing there are so many Daxamites for her to beat up when they're on the ship because they're perfect for venting her frustration. Even so, it gets a little annoying after what feels like the hundredth skull she's cracked because even though she knows he's somewhere onboard, she can't hear his heartbeat because of the stupid ship's design and material and she just wants to be sure that he's okay-

Oh. There it is. There _he_ is.

“Hi!” he says with a bright grin that is totally at odds with their current situation.

Rao, he looks hot in that outfit. She's actually having a bit of trouble breathing and she's sure her brain's short-circuited a little too.

“Hi!” she manages to respond somehow as he comes closer and the drumbeat thundering in her ears – is that his heart or hers, and does it matter? – picks up.

She could kiss him right now.

Oh. Right. Lena's here. And so are Lillian and Henshaw. _Get it together, Kara_ , she tells herself and blurts out the first thing that comes to mind. “Uh... Kara Danvers sent me to get you.”

...Wow, she sounds like an idiot.

“Yeah, she's... she's great, isn't she?” he responds equally breathlessly.

...Well, good to know she's not the only one then.

She can't help the giggle that escapes her lips. “Yeah, she'll be thrilled to hear you think so.”

Good god, there must be something in the air because she really did not just try to one-up his ridiculousness.

But then he looks into her eyes and she can almost hear him say, _You came after me._

 _Every time_ , she tries to communicate back through her smile.

Goal accomplished – minus kissing him, that is; she'll rectify that later – they leave... or would have if not for Lillian being the utterly predictable evil woman that she is. It's a good thing she and Winn planned for this although that proves to be the easy part.

Getting Mon-El to leave while she goes to confront Rhea alone is much harder. She can't even fault him for being so worried considering everything but she's confident she can handle it herself. Most of all, she needs to know that he's okay.

This time, she can take comfort in the fact that when she stops hearing his heartbeat it will be because he is safe and not because she's lost him for good.

(She will revisit this moment, days and weeks and months from now, and wonder if she'd cursed herself by having that thought.)

 

* * *

 

This is all so wrong. Everything is just so wrong. How did it all go _so wrong_?

Logically, Kara knows that they can't afford to waste a single second because every breath that Mon-El draws brings him one step closer to death and that is beyond unacceptable. His heartbeat still thunders in her ears but she can hear it slowly weakening and the rhythm is erratic instead of soothing.

Even so, she doesn't want to let go.

“I love you,” she whispers brokenly as she breaks the kiss, and it wasn't supposed to hurt when she finally said it but it does, _itdoesitdoesitdoes_ and _it won't stop hurting_. “And I should've said it before.”

She thinks he might be trying to smile but there is only pain etched across his face. “I love you,” he responds and it's not fair. It's not fair that saying it still comes so easily to him even when he's _dying_ and this is the last time she'll ever hear him say it.

It's not fair that this is the last _everything_ for them.

So she pours herself into the kiss even as she tries her hardest to pretend like this isn't goodbye – like the drumbeat she has come to associate with home is as strong as ever.

But it's not. There is no illusion to find refuge in and the reality of the situation rings loud and clear with every irregular thump of his heart.

It helps, even if only a little, to hear the beat start going back to normal the moment he activates the pod. He's going to be okay. He's going to live. It's going to have to be enough.

Despite that, she barely manages to keep herself standing as she watches him fly away, straining all the while to tune out every other sound around her just so she can keep hearing that drumbeat for just _one second longer_ -

-and then it's gone forever, and she falls to her knees as the silence swallows her whole.

 

* * *

 

She flies high, higher, the highest she can possibly go in some desperate misguided belief that if she tries hard enough, she can hear his heartbeat again. Just one more time.

All that greets her instead is the cold and empty stillness of space.

**Author's Note:**

> So this is apparently what happens when you rewatch Season 2 to get through the hiatus while also going on a Florence + The Machine marathon. On that note, if you've never heard of Florence + The Machine before, I wholeheartedly recommend the band. Cosmic Love is a good place to start as is Drumming Song which was in the fic in spirit. If you're already a fellow fan, can I get a "HELL YEAH!" from you?
> 
> Also, if I succeeded at adding a new layer of angst to canon in your eyes, I sincerely apologise... I say as I simultaneously laugh evilly and sob uncontrollably. (I really have no idea why I keep writing angst.) The next one will be pure fluff, I swear! (I feel like I've said this before...)


End file.
